Coal power plants (boiler and gasifiers) can have their efficiency improved from 1-5% by using on line pulse-combustion slag blasters to reduce or eliminate slag. Steady state soot blowers are not effective for most coals, where repetitive shock waves are necessary to minimize slag formation. Boiler heat cannot be effectively radiated or convected to boiler tubes covered with slag. Slag buildup is slated to increase in the future as different coals are burned and more efficient Nox cycles are incorporated. Slag removal efficiencies will lead to pervasive SO2 reductions of 75 pounds per ton of coal saved due to efficient slag removal. At a 1% improvement due to slag reduction, using the North American coal consumption, SO2 emissions will be reduced by 714 million pounds per year.